Jig for swivel links



June 28, 1949. c. s. TAGO 2,474,289v

JIG FOR SWIVEL LINKS Filed Aug. 13, 1946 mmvrok CA TAL/NO G. TAG-.0

A 'r'r'oeue v tothe link, isdifilcult to machine.

Patented June 28, 1949 UNITED STATLE S PATENT OFFICE JIG FOR SWIVEL LINKS Catalino G. Tago, Brooklyn, N. Y.

.Application-August 13, .1946, Serial No. 690,199

(Granted 'under the act of 'March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) This invention relates to a jig for holding a swivel link, and more particularlyto a jig for holding a swivel link and for spot facing a portion of the link -Whena chain is attached to a stationary object such as a'wall, it is sometimes necessaryto have the endlink,whichis secured to the wall,

swiveled so that if the chain is rotated, it willnot become twisted. Theend link has an enlarged section capable of providing a'bearing' surface for the'head of a swivel pin which is'inserted-through an Opening in the enlargedsection of the link. Thebearing surface, which is internal in relation Thepresent invention overcomes this difliculty'by providing a'jig comprising a movable yoked'member which engages the end of the swivel link opposite'to the enlarged section and which rotates the link against a cutter to machine thebearingsurface.

An object of this invention is to provide a jig for holding aswivel link and capable of rotating the swivel link while causing an internal portion 'of the enlarged section of the link to bespot faced.

Anotherobject is toprovide a jig of this type having a cutter detachably affixed to the jig so that'the internal portion'of the link to be spot faced canbe rotated in relation to the stationary cutter.

Another object is to provide a jig for holding and spot facing a swivel link, said jig having a replaceable guide shank for accommodating various sizes of links.

Further objects and advantages of this invention, as well as its construction, arrangement, and operation, will be apparent from the following description and claims in connection with the accompanying drawing, in which:

Fig. 1 is a view in elevation of a preferred form of the invention; and

Fig. 2 is a sectional view along line 22 of Fig. 1.

Jig II, which may be made of metal or any other suitable material, includes a foundation l2, which is a relatively large, substantially rectangular member. Foundation I2 has centrally located in top face I3 an opening I4, which is substantially square in shape and which extends through foundation I2. Foundation I2 includes side I5 in which is centrally located opening I6, substantially round in shape and having its axis intercepting and perpendicular to the vertical axis of opening I4.

Foundation I2 has removably attached to it, shank I1. Shank I1 is an elongated member,

round in cross-section having ends I-Band I9. End I8 is oifset so that it is substantially square in cross-section and is adapted to fit intoopening I4 of foundation '-I2 with a' relatively'tight fit. End I8 has located in-it opening 20, substantially round in shape and having the same diameter asopening It in foundation I2. Opening 29 is positioned so that when end'l8 of shank I I is inserted in opening M of foundation -I2'with which it mates, the axis 'of opening 20 0f end I8 is aligned with'the axis of opening it of'foundation I2. Shank ii is removably secured -to foundation 52 by means of pin 2|, which is adapted to be inserted'through openings It and 29 with a relatively tight fit.

EndiB of shank H has in it opening 22. -'Opening 22 is substantially round in cross-section'and extends through shank Hat a point adjacent to end I9.

Jig I i also includes cutter'23, which is a standardcylindrical cutting tool havingat one end cutting teeth 24. Extendingthrough cutter 2 3 along its cylindrical axis isopening25"centrally located in cutter 23 and having a diameter slightly larger'than that of shank I? so that'it can be slipped over shank il in a relativelytight sliding fit. Cutter '23 also has extendingtherethrough perpendicular to its cylindrical-axis'an openingzt substantially round in-'shape-an'd"of the same diameter as opening 22 in shank I! with which it is to be aligned. Cutter 23 is removably attached to shank H with teeth 24 facing foundation I2 by means of pin 21. Pin 21 is a cylindrical member having a diameter slightly smaller than opening 22 of shank I! and opening 26 of cutter 23 so it can be inserted through these openings in a friction fit.

Jig II also includes yoke 28, which is a relatively large furcated member having sides 29, top face 30 and bottom face 3|. Yoke 28 has slot 32 cut into and entirely across the bottom face 3|. Opening 33 is substantially round in shape and extends through yoke 28 from side to side and is perpendicular to the longitudinal plane of slot 32. The end of opening 33 is located on the vertical center line of face 29 and is adjacent to bottom face 3i. Yoke 28 is rigidly affixed at its top face 30 to shaft 34 adapted for connection with a source of power (not shown) that is capable of rotating shaft 34 and exerting a pull on it, thereby rotating and exerting a pull on loke 28. The axis of shaft 34 forms the axis of the complete jig and in assembled form is aligned with the longitudinal axis of link 38 and shank II.

Extending through. opening 63 of yoke 28 is pin 35. Pin 35 is substantially cylindrical and has a shank 36 and one end ofiset to form enlarged head 31. Pin 35 has a diameter slightly less than opening 33 of yoke 28 and is adapted to fit therein in a relatively tight friction fit with the inner face of enlarged head 31 bearing on side 29 of yoke 28.

Jig II is designated to operate on a piece of Work which is shown by way of illustration as being swivel link 38. Swivel link 38 is a chain link having one end enlarged to form section 39, through which is cut a central opening M! adapted to have inserted in it a swivel pin (not shown) for securing the link to an object.

Jig II is designed to hold link 38 and to spot face the inner portion or back face of enlarged section 39. To assemble the jig end 18 of shank H is first inserted into opening [4 of foundation i2 keeping the axis of opening l6 of foundation l2 and opening 20 of shank l'l aligned. Pin 2| is inserted through these openings to rigidly secure shank H to foundation l2.

Link 38 is then positioned on shank I! by inserting shank IT into opening 40 of enlarged section 39, keeping end iii of shank i'l protruding through enlarged section 39. Cutter 23 is then positioned on shank ll by inserting shank i! into opening 25 of cutter 23, keeping cutter teeth 24 in the downward position facing enlarged section 35 of link 38. Cutter 23 is then translated on shank H and rotated thereon until opening 26 of cutter 23 and opening 22 of shank H are aligned. Pin 2? is then inserted through the openings to secure cutter 23 rigidly in position on shank ll.

Yoke 28 is positioned with relation to link 38 by fitting link 38 into slot 32 so that opening 33 in side 29 of yoke 28 is clear with respect to link 38. Shank 36 of pin 35 is inserted through opening 33 and. link 38 until the inner face of head 37 bears on side 29 of yoke 28 thereby afiecting engagement of yoke 28 and link 38.

In operation when shaft 34 is rotated and pulled upon, link 38 also rotates and has a pull exerted on it. Cutter teeth 24 then come into contact with the inner face of enlarged link section 39. Enlarged link section 39 rotates in relation to stationary cutter 23 and this results in spot facing oi the inner portion of section 39 by the action of cutter teeth 24 upon section 39. Shank I1 is removably aihxed to foundation I2 that it can be replaced with shanks of varying diameter for accommodating diiferent sizes of swivel links. Jig I I can be modified so that yoke 28 remains stationary while shank IT and cutter 23 aiiixed thereon rotate in relation to enlarged section 39 of swivel link 38.

It is to be understood that various modifications and changes may be made in this invention without departing from the spirit and scope thereof as set forth in the appended claims.

The invention described herein may be manufactored and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is:

1. A jig for use in tooling a swivel link having a swivel-axis bore through one end, said jig comprising a shank for extending in axial and rotary sliding movement through the link bore, a tool fixedly mounted on the end of the shank extending into the link, said tool facing the link at the inner end of the link bore, means for supporting the end of the link opposite to the bore end, and means for locking the supporting means and link together for rotational movement.

2. In combination with a swivel link having a swivel-axis bore through one end, a jig for tooling said link, said jig comprising a shank for extending in axial and rotary sliding movement through said link bore, a tool fixedly mounted on the end of said shank extending into said link, said tool facing the link at the inner end of the link bore, means for supporting the end of said link opposite to the bore end, and means for locking the supporting means and link together for rotational movement.

CATALINO G. TAGO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,491,577 Baldwin Apr. 22, 1924 1,590,201 McGuckin June 29, 1926 

